Process of treating cellulose fibers



Patented July 9, 1935 raocsss or v TREATING- CELLULOSE FIBE Fredrick Olsen'and Frederick R. Seavey, Dover,

N. .L, assignors to The Cellulose Research Corporation, a corporation of Delaware No Drawing. Application February 13, 1029,

1 Serial No. 339,732

'7 Claims.

(Filed but not issued under the act or Match 3, 1883, as amended April so, 1928; 370 0. G. 157) The invention described herein may-be manuiactured and used by us for the Government for governmental purposes, without the payment .to us of anyroyalty thereon. i

This inventionrelates cellulose fibers. In the preparation of nitrocellulose explosives,

the cellulose is nitrated in a bath of. nitric and sulphuric acid. When removed from the bath,

the tubular fibers carrying both adherent or me.- chanically-held acid and adsorbedacid as well as other impurities must'be subjected to a purification treatment to remove, these unstable lower nitro bodies.

The principal object of this invention is the reduction-of the. fibers to a physical condition which will'be favorable for the action of the purifying or neutralizing agents. This object is lar structure would be compressed or collapsed by the pressure fluid medium and, since the tube is not filled with the fluid, there can be no balancing of interior andexterior pressures pre-' liminary to the reduction of external pressure. It is, therefore, proposed to preparethe tubular fibers against collapse by filling them with a relatively incompressible fluid. ,This condition of the fibers may be produced by allowing them to become saturated with a liquid, conveniently trapped airirom the fibers by the application of a vacuum.

The fibers thus prepared are placed in a high pressure chamber and a fluid of high temperature such as steam is admitted to the chamber under a pressure of 500 to 1000 pounds per square inch and for varying from five seconds to a process of treating to one minute, depending upon the degree of physical disruption it is desired to secure. Upon suddenly relieving the pressure 'as by discharging the fibers through an opening in' the chamher, the fiuid in the fibers which has been heated bythe pressure medium is rapidly converted into steam causing disruption of the fibers.

Weclaim: 7, l 1. The step in the preparation of smokeless powder which consists in'filling each fiber of a mass of collapsible cellulose fibers with a re1a-' tively incompressible medium, subjecting them to a high temperature pressure fluid and suddenly releasing the pressure.

2. The step in the preparation of smokeless powder which consists in filling each fiber ot a mass of collapsible cellulose fibers with a supporting medium, subjecting them to a high temthe pressure.

,3. The step in the preparation of smokeless powder'which consists in placing the fibers 0! a mass of collapsible cellulose fibers in a non-collapsible condition, subjecting them to internal and external pressure and suddenly releasing the external pressure. 1

4. The step in the preparationpf smokeless powder which consists in fillingeach fiber of a mass of collapsible cellulose fibers with a medium ;'capable of suddenly changing its state and thereby producing a pressure within each fiber and ms) T TES: mini perature pressure fiuid and suddenly releasing- 7 then causing the medium to suddenly change its state whereby the fibers are disrupted.

5. The process or producing cellulose pulp comprising providing cellulose in the form oiseparate tubular fibers, saturating said fibers with an incompressible liquid so as to fill said fibers withsaid' liquid, then. subjecting said fibers to high pressure and temperature, and then suddenly relieving said pressure to cause disruption t of said fibers by the vaporization of said liquid. and also optionally by removing the en- 6. The process of producing cellulose pulp 7. The process of producing cellulose -pulp then subjecting said fibers to high pressure and comprising providing cellulose in the form of sep-' temperature, and then suddenly relieving said arate tubular fibers. subjecting said fibers to appressure to cause disruption of said fibers by vaplication of a vacuum for removal or air, then porization 01 said liquid.

5 saturating said fibers with an incompressible liq- FREDRICH OLSEN. B

uid so as to fill said fibers with said liquid, and FREDERICK R. BEAVEY. 

